Metal-drawing die



(Model.) I

G. E. THACKRAY. METAL DRAWING DIE.

No. 546,202. Patented Sept. 10,1895.

ANDREW IGHMIAM. PHUTO-UYNIIWASHI N GI'D ll D.C

Uivrrnp STATES PAT NT @rrrcn.

GEQRGE E. THAOKRAY, OF NESTMONT, PENNSYLVANIA.

M ETAL-DRAWI NG DIE.

SPECIFICATIGN forming part of Letters Patent No. 546,202, dated September 10, 1895.

Application filed April 17,1395. Serial No. 546,107. (Model) To all whom it may concern.-

Be it known that I, GEORGE E. THACKRAY, a citizen of the United States, residing at Nestmont, in the county of Cambria and State of Pennsylvania, have invented certain new and useful Improvements in Metal-Drawing Dies; and I do hereby declare the follow ing to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

- The object of my invention is to provide new and improved forms of sectional or adjustable drawing-dies for use in drawing metal rods or bars forthe purpose of giving their surfaces an accurate form and finish or for increasing their strength and elastic limit or for successively reducing the section, as in wire-drawing.

My invention has special reference to dies for drawing rectangular or square bars, rods, or wire, although it may also be adapted and applied for use in drawing other bars of regular or irregular polygonal or other section, as may be readily understood.

Although my invention may be adapted for use in drawing rods or bars of various crosssections, as above described, in order to simplify my descriptioml will refer herein onlyto that form which isadapted for use in drawing square or rectangular bars, the adaptation and arrangement for other sections than these being obvious.

My improved die'consists of four die-blocks of substantially rectangular outline, each block being formed, however, with one of its edges convex or rounded, which edge serves as the working face. One of the ends of each of the die-blocks is concave to conform to the.

convexity of the side of one of its adjoining die-blocks, all of which are so grouped about a common center as to form a rectangular opening, bounded by the convex sides of the four die-blocks. The die-blocks may be made of such length that by adjusting their position with respect to one another the aforesaid opening may be made larger or smaller within reasonable limits, as the necessities of the work may require. The edge of each dieblock opposite to its convex edge I prefer to make with a plane surface, against which one side of a wedge takes abearing, the other side of the wedge being supported by a suit able surface formed therefor in the die-plate. These wedges may either be so proportioned as to be held in position by frictional contact with the surfaces against which they work or they may be provided with bolts, the nuts of which bear against the die-plate for the purpose of securing the wedges in the desired position, whereby the die-blocks may be adjusted and firmly held in and to said dieplates. In addition to the above-described wedges which bear against those edges of the die-blocks opposite their convex or working faces I also provide other wedges of similar construction and arrangement which bear against those ends of the die-blocks opposite to their concave edges, these latter wedges serving to keep the parts together and exerting a pressure in a direction substantially at right angles to that of the previouslydescribed wedges. The adjustable die-blocks and wedges are all contained in and supported .by a die-plate or draw-plate, preferably circular in outline, having the general form of a truncated segment of a sphere, the spherical surface of which is supported in a suitablyshaped recess formed in the head-block of a drawing-machine, thus acting as a ball and socket, in order to provide a ready means of aligning the axis of the dies with relation to the line of'action of the drawing power. In order to provide suitable clearance space for the small ends of the wedges, and also to provide a proper and easily-renewable bearingblock for the inner surface of my die-blocks, I provide a backing'plateof rectangular or other suitable outline having a hole therethrough conforming to but somewhat larger than the opening in the die-blocks, said backing-plate being placed between the inner surfaces of the die-blocks and that of the die-plate. I provide several of these backing-plates with holes of different sizes made to conform to the different sizes of bars which may be drawn in one set of dies, the inner edges of the surfaces of the holes of these backing-plates registering with the inner edges of the die-blocks in such a way as to firmly and securely support the latter during the operation of drawing a bar. I do not, however, consider this back ing-plate as an essential feature of my invention, as I can arrange the die-blocks directly against the inner face of the die-plate, which in this case is provided with holes somewhat larger than necessary in the previous case in order to accommodate the ends of the wedges, as may be readily understood; or, in other words, the backing-plate and the die-plate may be formed in one piece instead of separately, as described and shown.

Although I have shown and described the wedges formed with bolt-ends for adjusting my die-blocks, I do not limit myself to this exact construction, as I may use wedges without the bolts, or set-screws working in threaded holes formed in the die-plate and bearing against the edges of my adjustable die-blocks, or a plate containing a spiral groove or series of same in connection with pins or studs formed on the die-blocks, said grooved plate being attached to the dieplate by means of a screw-thread, after the manner of lathe-chuck constructions; or, again, I may use a threaded tapering sleeve, to the interior conical. surface of which the outer edges of the die-blocks are fitted; or, in fact, anysuitable means for adjusting and holding the die-blocks in a suitable position with relation to one another, as may be readily understood.

Having given this general description of my invention,I will now refer to the annexed sheet of drawings, which form part of this specification, and in which like letters refer to like parts.

Figure 1 is a front elevation showing my die-blocks, adjusting-wedges, and die-plate, the die-blocks in this figure being adjusted to form a square bar of small cross-section. Fig.

2 is an elevation similar in all respects to Fig. 1, with the exception that in this case the same die blocks are shown, adjusted to produce a square bar of larger section than shown in Fig. 1. By a different adjustment of the wedges a rectangular section may also be shown. Fig. 3 is a cross-section on the lines 3 3 of Fig. 2. Fig. 4 is a separate view of one of my die-blocks, showing its convex working face and its adjoining concave face. Fig. 5 is a cross-section taken on the lines 5 5 of Fig. 4.

In the different figures A A A A are my dieblocks, provided with convex surfaces B. O is the die-plate; K the spherical surface of the same, and I I are elongated holes formed in the die-plate 0, through which the bolts of the adjusting-wedges project.

D D D D are adjusting-wedges bearing against the die-plate C and the side edges of the die-blocks A A A A, while E E E E are similar wedges which bear against the ends of said blocks.

F F are bolts which form part of the wedges, being provided with nuts G G, which nuts bear against the washers J J, placed over the slotted holes I I, above described.

His a bearing-block fitting between the dieplate 0 and the die-blocks A A A A, and provided with a hole, as shown, said hole being approximately the same size and shape as that formed by the outer working surfaces of the die-blocks when adjusted for the size with which said bearingblock is designed to be used. I

Referring now to Figs. 4 and 5, which are detached views of one of my die-blocks, B is the convex working-face, and L is the adjoining concave face made to conform to the convexity of the contiguous die-block.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. A die composed of a number of blocks,

each having a convex working face and a concave face immediately adjoining the same; said concave face being made to conform to and fitting the convexity of the adjoining block, all being so grouped as to form a draw hole, substantially as set forth. 2. A die composed of a number of blocks, each having a convex working face and a con cave face immediately adjoining the same; said concave face being made to conform to and fitting the convexity of the adjoining block, in combination with a die plate and means for securing said die blocks therein, substantially as set forth.

8. Adie composed of a number of blocks, each having a convex working face and a concave face immediately adjoining the same: said concave face being made to conform to and fitting the convexity of the adjoining block, in combination with a die plate, wedges bearing against the outer edges of the die blocks, and means for adjusting said wedges, substantially as set forth.

4. A die composed of a number of blocks, each having a. convex working face and a concave face immediately adjoining the same; said concave face being made to conform to and fitting the convexity of the adjoining block, in combination with a die plate, and wedges bearing against the outer edges of the die blocks, said wedges being adjustable by means of threaded bolts, the nuts of which bear against said die plate, substantially as set forth.

5. A die composed of a number of blocks, each having a convex working face and a concave face immediately adjoining the same; said concave face being made to conform to and fitting the convexity of the adjoining block, in combination with a die plate, wedges bearing against those edges of the die blocks, opposite their convex working faces, other wedges bearing against those edges of the die blocks opposite their concave faces, and means for adjusting said wedges, substantially as set forth.

6. A die composed of a number of blocks, each having a convex working face and a concave face immediately adjoining the same; said concave face being made to conform to and fitting the convexity of the adjoining block, in combination with a die plate and a backing plate interposed between the die plate and the die blocks, said backing plate and the surfaces of said opening, and provided with screw ends and nuts; said screw ends passing through slotted holes in said die plate, and secured to said'plate by nuts, substantially as set forth.

In testimony whereof I affix my signature in the presence of two witnesses.

v GEORGE E. THACKRAY.

' Witnesses:

H. A. SHIELDS, R. B. EISENBERG. 

